London, Nov. 8 (Reuters): Finance minister Gordon Brown, Britainís premier-in-waiting, has been contacted by police investigating allegations his Labour Party awarded state honours in return for cash, a government source said today.

Two other senior Labour figures, a minister and former minister, said they had been asked to give evidence recently. The revelations that detectives have contacted such senior party figures have fuelled speculation they will soon question Prime Minister Tony Blair.

The row over cash-for-honours blew up earlier this year after it was disclosed that rich businessmen had been nominated for seats in Britainís unelected upper house of parliament after lending Labour large sums for its 2005 election campaign. The police are investigating whether political parties broke a 1925 law banning the sale of state honours.

Police want to know if ministers knew four businessmen who loaned Labour millions of pounds had been put forward by Blair for seats in the House of Lords ó known as peerages. The furore has led to demands for reform of political party funding in Britain and heaped pressure on Blair to step down.

The Prime Minister has already said he will resign next year. Brown, tipped to take over from Blair, was asked by police in a letter to provide written evidence into what he knew of the loans and Lords nominations, the source said.